underscore-es

__
/\ \ __
__ __ ___ \_\ \ __ _ __ ____ ___ ___ _ __ __ /\_\ ____
/\ \/\ \ /' _ \ /'_ \ /'__\/\ __\/ ,__\ / ___\ / __\/\ __\/'__\ \/\ \ /',__\
\ \ \_\ \/\ \/\ \/\ \ \ \/\ __/\ \ \//\__, \/\ \__//\ \ \ \ \ \//\ __/ __ \ \ \/\__, \
\ \____/\ \_\ \_\ \___,_\ \____\\ \_\\/\____/\ \____\ \____/\ \_\\ \____\/\_\ _\ \ \/\____/
\/___/ \/_/\/_/\/__,_ /\/____/ \/_/ \/___/ \/____/\/___/ \/_/ \/____/\/_//\ \_\ \/___/
\ \____/
\/___/

Underscore.js is a utility-belt library for JavaScript that provides
support for the usual functional suspects (each, map, reduce, filter...)
without extending any core JavaScript objects.
It's available in _ES6_ and _UMD_ (_cjs_, _amd_, _iife_) formats

ES6 & Beyond usage:

- partial importation of features (just import what you need, with a name that suits you).

``js
import _template from 'underscore-es/template';

var basicTemplate = _template("Ok, i use <%= builder %> for my es6 and beyond stuff !");
var result = basicTemplate({builder: 'rollup'});
console.log( result );
// => "Ok, i use rollup for my es6 and beyond stuff !"
`
__nb__: only _chain isn't available in this case.

another way to use chaining feature here is through _compose or _use.
`js
import _use from 'underscore-es/use';
import _initial from 'underscore-es/initial';
import _filter from 'underscore-es/filter';
import _union from 'underscore-es/union';
import _last from 'underscore-es/last';

function note (num) {return 'result: '+ (num + 10) + " / 20"}
var test = _use([1, 2, 3, 6, 9])
.do(_union, [1, 3, 11], [2, 6])
.do([], Array.prototype.concat, [10, 14]) // or simply .do([], [].concat, [10, 14])
.do(_filter, (num) => num % 2 == 0)
.do(_initial)
.do(_last)
.do(note)
.value();
console.log( test );
// => result: 20 / 20
`

import features depending of their category
`js
import * as $co from 'underscore-es/_collections';
import * as $ar from 'underscore-es/_arrays';
import * as $ob from 'underscore-es/_objects';
import * as $fu from 'underscore-es/_functions';
import * as $ut from 'underscore-es/_utilities';

console.log( $ar._union([4,7], [7,0,3]) );
// => [4, 7, 0, 3]
`

- global importation of all features

`js
import _ from 'underscore-es'; // or from 'underscore-es/_namespace'

_.chain([4,7])
.union([7,0,3])
.initial()
.reverse()
.head()
.value()
// => 0
`

- breaking changes

Since this underscore source code has been rewritten to be more es6 friendly :

the _.templateSettings property is now _.template.settings

`js
import _template from 'underscore-es/template';

_template.settings = {
evaluate: /\{\{([\s\S]+?)\}\}/g,
interpolate: /\{\{=([\s\S]+?)\}\}/g
};

var custom = _template('

{{ for (var key in people) { }}
• {{= people[key] }}
{{ } }}

');
var result = custom({people: {moe: 'Moe', larry: 'Larry', curly: 'Curly'}});
console.log( result );
// =>

• Moe
• Larry
• Curly

`
the _.iteratee shall now (for global importation) be overwritten through _.setIteratee([fn]) method
`js
import _iteratee, {_setIteratee} from './underscore-es/iteratee';
import _countBy from './underscore-es/countBy';
import _isRegExp from './underscore-es/isRegExp';
import _filter from './underscore-es/filter';

_setIteratee( function(value) {
// RegEx values return a function that returns the number of matches
if (_isRegExp(value)) return function(obj) {
return (obj.match(value) || []).length;
};
return value;
});

// test some methods that claim to be transformed through _iteratee
var collection = ['foo', 'bar', 'bbiz'];
console.log(_countBy(collection, /b/g))
// => {0: 1, 1: 1, 2: 1}
console.log(_filter(collection, /b/g))
// => ['bar', 'bbiz']
``

Documentation is the place to find what you need to know !

This project adheres to a code of conduct. By participating, you are expected to uphold this code.

For support and questions, please use
the gitter channel
or stackoverflow

Underscore is an open-sourced component of DocumentCloud:
https://github.com/documentcloud

Many thanks to our contributors:
https://github.com/tnga/underscore-es/contributors
https://github.com/jashkenas/underscore/contributors